A. Field of the Invention
The field of the present invention relates generally to door hinges utilized to pivotally attach a door to a framework or other structure. More particularly, the present invention relates to door hinges that are lockable to prevent the door from swinging open. Even more particularly, the present invention relates to such locking door hinges that utilize a locking pin to prevent the pivoting components of the hinge from rotating relative to each other to lock the door in a closed, partially open or open position.
B. Background
Door hinges are commonly utilized with interior and exterior doors to pivotally attach the door to the door framework or jamb to allow persons to swing the door between the open or closed positions. Although a variety of different types of hinges are utilized with doors, one common type of door hinge is the butt hinge. The butt hinge generally comprises a pair of generally rectangular leaves that are joined together with a metal rod or pin that passes through engaged barrels on the proximal end of the leaves. One leaf attaches to the door and the other attaches to the framework, typically utilizing screws placed through apertures in both of the leaves. When the door is closed the leaves meet and only the barrels and pin are visible, which is one of the popular features of butt hinges.
Numerous mechanisms are available for locking a door in its closed position or a partially closed position. One common type of apparatus for locking a door comprises a locking mechanism disposed in the door handle or knob that engages a portion of the handle/knob to prevent a person from turning or rotating the handle/knob and opening the door. Another common door locking apparatus is commonly referred to as a deadbolt lock, which typically comprises a locking mechanism on the door, which may be separate and spaced apart from the door handle/knob, that is configured to extend an relatively strong elongated member into a cavity in the door framework in a manner that prevents the door from opening. Other common types of door locking apparatuses include various styles of barrel or pin locks, chain locks and latches. Generally, the primary purpose of these door locks is to prevent unauthorized entry into a building or room by preventing a person from opening or at least fully opening the door.
Another common use for door locks is to keep a person, such as a young child, in a building or room by preventing them from fully opening the door. One problem with many of the available door lock systems is that they are often positioned relatively low on the door or framework such that a child can reach the door lock, unlock the locking mechanism and open the door. Doing so can allow the child to leave the building/room without permission or allow an unauthorized person, such as a stranger, to enter the building/room, both of which can have dire consequences for the child and/or others. Some of the existing door locks, such as the chain and latch types of locks, are configured such that they can be placed relatively high on the door or framework so a small child cannot reach the lock and unlock it. Placing the lock high on the door, however, makes it very difficult if not impossible for a handicapped (i.e., wheelchair bound) person to reach the lock to lock or unlock the door. Unless two locks are purchased and installed on the door, with one placed high and the other placed low, the user must decide ahead of time if he or she is primarily concerned with preventing a child from reaching the lock or allowing a handicapped person to reach the lock.
Another type of door locking apparatus is the locking door hinge. In general, such apparatuses work with or utilize part of the door hinge to lock the door. For instance, U.S. Pat. No. 1,092,926 to Madsen describes a locking hinge having an opening in one leaf through which a portion of an upstanding lug on the other leaf protrudes when the door closes and the two hinge leaves abut so that a tapered key can be inserted in a slot in the portion of the lug protruding through the opening to prevent the door from being opened. U.S. Pat. No. 3,263,269 to McGahee describes a safety hinge having a retainer device that is attached to the door or framework in a manner that prevents the pintle from being removed from the hinge, which would allow the door to be removed. U.S. Pat. No. 3,805,325 to Lee describes a separable hinge having a hasp loop projecting from one leaf and a hasp strap secured to the pintel such that when the hasp strap is engaged over the hasp loop and a pin or the like is engaged in the hasp loop the hinge is secured in an assembled relationship. U.S. Pat. No. 6,151,757 to Beals, Jr. et al. discloses a lockable piano-type hinge assembly having a locking hinge piece, which comprises the hinge pins, with an opening that is aligned with a locking loop that extends from the hinges pieces having the pin barrels such that the locking loop protrudes through the opening so the user may attach a locking device thereto in order to prevent the hinge from opening unless the locking device is removed.
Despite the advancements offered by the prior art patents, what is needed is an improved locking door hinge apparatus that selectively prevents opening the door. The preferred locking door hinge should be configured to secure the door in closed position or, if desired in a partially open position, in a manner that prevents unauthorized opening of the door. Preferably, the locking door hinge would be relatively easy to manufacture, simple to use and adaptable to a wide variety of hinges and doors. The preferred locking door hinge should be suitable for use as one or more of the door hinges, including the upper and lower door hinges, to selectively prevent small children from being able to open the door or allow wheelchair bound persons to engage or disengage the locking mechanism. Preferably, an improved locking door hinge would allow a person to easily and quickly lock a door to prevent opening or complete opening of the door from inside a room or structure without the use of keys, latches, locks or the like.